Uno S, Nakamura M, Seki T, Ariga T
Department of Nutrition and Physiology, Nihon University College of Bioresource Sciences, Tokyo, Japan.
Biochem Biophys Res Commun. 1997 Oct 9;239(1):123-8. doi: 10.1006/bbrc.1997.7440.
Early growth response with respect to tissue-type plasminogen activator (tPA) and type-1 plasminogen activator inhibitor (PAI-1) gene expression was studied in rat hepatocytes in primary culture. The genes for tPA and PAI-1 could be categorized as a delayed early growth response (DER) gene and an immediate early growth response (IER) gene, respectively. The expression of tPA was much higher in growth-promoting than in static culture conditions (i.e., cultured at low density and/or on a collagen-coated dish), and that of PAI-1 was regulated in the opposite direction. Experiments using dibutyryl cAMP (dbcAMP) and H-89 showed that the cAMP/A-kinase system might be involved in the induction of the early growth response of tPA and in the augmentation of PAI-1 mRNA induction by dbcAMP. These fibrinolytic components, whose expression is closely associated with hepatocyte growth, may play important roles in pathophysiological events in the liver such as liver regeneration.
在原代培养的大鼠肝细胞中，研究了早期生长反应与组织型纤溶酶原激活物（tPA）和1型纤溶酶原激活物抑制剂（PAI - 1）基因表达的关系。tPA和PAI - 1的基因可分别归类为延迟早期生长反应（DER）基因和即刻早期生长反应（IER）基因。在促进生长的培养条件下（即低密度培养和/或在胶原包被的培养皿上培养），tPA的表达比静态培养条件下高得多，而PAI - 1的表达则呈相反方向调节。使用二丁酰环磷腺苷（dbcAMP）和H - 89的实验表明，cAMP/A激酶系统可能参与tPA早期生长反应的诱导以及dbcAMP对PAI - 1 mRNA诱导的增强作用。这些纤溶成分的表达与肝细胞生长密切相关，可能在肝脏再生等肝脏病理生理事件中发挥重要作用。
